High-Spatial-Diversity Imaging Receiver Using Fisheye Lens for Indoor MIMO VLCs

This letter proposes an imaging receiver scheme for an indoor multiple-input-multiple-output (MIMO) visible light communication (VLC), in which a fisheye lens with ultrawide field-of-view is used for high-quality imaging, so it can realize omnidirectional receiving and provide high-spatial diversity for decoding of the MIMO signals. In addition, the fisheye lens projects planar and small-sized images, which means that the integration with compact planar receiver array is feasible. Using the polynomial projection model, the optical intensity on the receiving plane is obtained, which is in accordance with the experimental result and shows that the images of the light-emitting diodes are clearly separated. The simulation results indicate that low correlations of the channel matrix are achieved, so high spectral efficiency is realized with various receiver positions under indoor circumstance. Consequently, this fisheye-lens-based imaging receiver is a potential candidate for high-performance indoor MIMO VLC applications.